Stopping and starting system



June 27, 1961 Filed June 9, 1960 D. P. GROVER STOPPING AND STARTINGSYSTEM 3 Sheets-Sheet 1 F g I g a 9mm I m o l 0 T' T rfi rfl 8 (it 3 @i)Q) I I? 5 m 3 INVENTOR.

BY ED111116 P- EITDVE'T June 27, 1961 2,989,900

D. P. GROVER STOPPING AND STARTING SYSTEM 3 Sheets-Sheet 2 1 Filed June9, 1960 FjgiL v INVENTOR.

' ,1 wk QAQWZ June 27, 1961 D. P. GROVER 2,989,900

STOPPING AND STARTING SYSTEM Filed June 9, 1960 3 Sheets-Sheet 3 IN V ENTOR.

United States Pater g 2,989,900 p STOPPING AND STARTING SYSTEM Donald P.Grover, Chicago, 111., assignor, by mesne assignments, to the UnitedStates of America as represented by the Secretary of the Army Filed June9, 1960, Ser. No. 35,098 2 Claims. ('Cl. 8912) This invention relates tomachine guns and more particulanly to a brake-starter device for guns ofthe Gatlingtype.

-Machine guns of the Gatling-type include a plurality of barrels whichare mounted to a rotatable cage. Consequently, when a gun of this typeincludes five or six barrels, the inertia of the rotatable cage mass isconsiderable and, as a result, the gun is either relatively slowaccelerating to operating speed or the motor for rotating the page massis overpowered with a corresponding increase in size and mass if quickacceleration is to be effected solely by the motor.

' Such a gun, too,-must be braked to a quick stop at the end of eachburst to prevent excessixe overrun whereby a large number of livecartridges would be cycled through the gun unfired and, when a gun isdriven by an electric motor, this means the addition of a braking systemto the Moreover, if a gun is self-energized by an integral, gas-poweredmotor, starting means must be provided to successively move one of thebarrels to the firing station for discharge of the cartridge chamberedin such barrel before power can be produced by the gun for energizingthe drive motor.

It is, therefore, one object of this invention to provide an auxiliarytorque means which temporarily cooperates with the operating motor of aGatling-type machine gun for starting rotation of the gun andaccelerating the gun to operating speed.

It is another object of this invention to provide such a torque devicefor both starting and stopping a Gatlingtype gun.

a It is still another object of this invention to provide such abrake-starter device which is energized while braking the gun, storesthe energy for later use and resupplies it to the gun to assist thedrive motor thereof in accelerating the gun to operating speed.

The specific nature of the invention as well as other objects andadvantages thereof will clearly appear from a description of a preferredembodiment as shown in the accompanying drawings in which:

FIG. 1 is a side view of a Gatling-type machine gun which has beenpartially broken away to show the brakestarter device assembled thereto;

FIG. 2 is a view taken along line 2-2 of FIG. 1;

FIG. 3 is a view taken along line 33 of FIG. 1;

FIG. 4 is a schematic view of the brake-starter device showing therelationship of the parts when the gun is operating and the torsionspring is relaxed; and

FIG. 5 is a view similar to FIG. 4 but showing the relationship of theparts when the coupler is engaged and the torsion spring wound up withthe energy therein stored for starting the gun when the coupler isdisengaged.

Shown in the figures is a machine gun 12 which is of a Gatling-type and,therefore, includes a receiver 14 to which there is rotatingly mounted acage 16 with six barrels 18 assembled thereto. Cage 16 is rotated by adrive motor 20 which may be energized by forces produced during firingof gun 12 or by external means and which is connected to the cage by agear train including a spur-gear 22 coaxially mounted on the cage andfixed thereto.

A starter-brake device 24 is mounted on the outside of receiver 14 andincludes a housing 26 for inclosing a transmission mechanism 27.Transmission mechanism 27 includes a longitudinally disposed shaft 28which is rotatingly journaled in housing 26 and fixedly mounted on therear end of such shaft is a first gear 30 disposed for meshingengagement with spur-gear 22. A second gear 32 is fixedly mounted on thefront end of shaft 28 so as to rotate with first gear 30.

An axle 34 is rotatingly journaled in housing 26 parallel to shaft 28and fixedly mounted on such axle is a third gear 36 which has meshingengagement with spurgear 22. A torsion rod 38 is journaled in housing 26and extends forwardly through the front end thereof in axial alignmentwith axle 34. The portion of torsion rod 38 which extends from housing26 is encased in a torsion tube 40. The front ends of torsion rod 38 andtorsion tube 40 are integrally joined so as to form a unitary torsionspring 42 the effective length of which is the total length of thetorsion tube and rod. A flange 44 is fixed to the rear end of torsiontube 40 and is joined to housing 26 to anchor one end of torsion spring42 thereto. Fixedly mounted on torsion rod 38 within housing 26 is anoverrun clutch 46 which carries a fourth gear 48 having meshingengagement with second gear 32. Overrun clutch 46 is designed totransmit the torque in torsion spring 42, after being wound up, ashereinafter described, to fourth gear 48 and through second gear 32 andfirst gear 30 to spur-gear 22 for starting gun 12. Overrun clutch 46,however, permits fourth gear 48 to overrun torsion rod 38 after torsionspring 42 is unwound.

Axle 34 is connectable to torsion rod 38 by a cylindrical,ratchet-toothed coupler device 50 which includes a primary member 52fixed to the front end of axle 34 and a secondary member 54 which ismounted to the rear end of torsion rod 38 by spline means 56. Whereby,secondary member 54 is displaceable along torsion rod 38 between anengaged and a disengaged position. Engagement is made between primarymember 52 and secondary member 54, when the secondary member is in theengaged position, by cooperating ratchet-type teeth 58 which areprovided on the facing sides of the primary and secondary members. Theteeth 58 are formed so that the torque in cage 16 is transferablethrough axle 34 to torsion rod 38 for winding up torsion spring 42.

Secondary member 54 is displaceable between the engaged and disengagedpositions by an electric, springbiased solenoid 60 which is ofconventional design and is connected to the secondary member by means ofa pivotal fork 62 which has sliding engagement with an annular channel64 provided around the secondary member. Solenoid 60 is connected byelectrical means to the electrical firing mechanism (not shown) of gun12 so as to be energized therewith when the firing mechanism istriggered to start gun 12 and thereby simultaneously actuate secondarymember 54 to the disengaged position. When the firing mechanism isde-energized to stop gun 12, solenoid 60 is deenergized therewithwhereby the integral spring therein actuates secondary member 54 to theengaged position.

Thus, during operation of gun 12, the gears 30, 32, 36 and 48 are allrotated by spur-gear 22, as shown in FIG. 4, with fourth gear 48overrunning torsion rod 38 and secondary member 54 disengaged fromprimary member 52.

When the firing mechanism of gun 12 is tie-energized to stop the firingthereof, solenoid 60 is simultaneously de-energized and thereby actuatessecondary member 54 to the engaged position to connect axle 34 totorsion rod 38. Whereby, the energy in cage 16 winds up torsion spring42 with fourth gear 48 still overrunning torsion rod 38 opposite to thewinding rotation of torsion spring 42. When the energy in cage 16 istransferred to torsion spring 42, gun 12 is stopped. Whereupon, torsionspring 42 tries to unwind but cannot as long as coupler device 50 isengaged because overrun clutch 46 makes connection between rod 38 andfourth gear 48 when the rod isrotated in the direction of the unwindingof the torsion spring and because of such connection, third gear 36,which is connected directly to such rod through the coupler device,rotates in one direction while first gear 30 is driven in the oppositedirection by the engagement of fourth gear 48 with second gear 32.Consequently, as first gear 34? and third gear 36 are both in meshingengagement with spur-gear 22, torsion spring 42 is prevented fromunwinding and thereby the energy remains stored therein until couplerdevice 50 is disengaged by solenoid 60.

When the firing mechanism of gun 12 is triggered to initiate a burst,solenoid 60 is simultaneously energized therewith to actuate engagingmember 54 to the disengaged position and thereby releases torsion rod 38from axle 34. Thereby, torsion spring 42 is free to unwind and, becauseoverrun clutch 46 drives in the direction of unwinding, the energy inthe torsion spring is transferred through gears 43, 32 and 30 tospur-gear 22 with the direction of the unwinding of the torsion springbeing reversed by the inter-position of first gear 30 and second gear 32between fourth gear 48 and spurgear 22. Whereby spur-gear 22 isenergized by torsion spring 42 in the direction of operation to assistdrive motor 20 in accelerating gun 12 to operating speed. If drive motor20 is energized by gun 12 tension spring 42 will rotate cage 16, ashereinbefore described, to bring the succeeding barrel 18 into positionfor firing the cartridge therein and so initiate a burst.

Torsion spring 42 may be any other type which is compact in size,adapted to store considerable energy and is energized by rotary means.

From the foregoing it is seen that there is herein provided for aGatling-type machine gun a simple brakestarter device which removesenergy from the gun to brake it to a stop, stores the energy for lateruse, and resupplies the energy to the gun when needed.

Although a particular embodiment of the invention has been described indetail herein, it is evident that many variations may be devised withinthe spirit and scope thereof and the following claims are intended toinclude such variations.

I'claim:

1. In a machine gun having a rotary cage with a spur- 4 gear coaxiallyand fixedly mounted thereon and a pinrality of barrels supportedthereby, a drive motor for rotating the barrels successively to a firingstation, a brake-starter device including a housing in which there isjournaled a longitudinally disposed shaft and an axle disposed parallelthereto, a first gear fixedly mounted on one end of said shaft formeshing engagement with the spur-gear, a second gear fixedly mounted onthe opposite end of said shaft, a third gear fixedly mounted on saidaxle for meshing engagement with the spurgear, a torsion spring havingone end anchored to said housing and the free end disposed within saidhousing adjacent said axle and in axial alignment therewith, a couplerdevice interposed between said axle and said torsional spring forreleasably connecting said shaft to the free end thereof to wind saidtorsional spring for transferring thereto after the firing of the gun isstopped the energy in said cage, an overrun clutch mounted on the freeend of said torsion spring, a fourth gear carried by said overrun clutchand disposed for meshing etigagement with said second gear, said overrunclutch being designed to transmit the torque of said torsion spring tosaid fourth gear when unwinding and permit said fourth gear to overrunsaid torsion bar after being unwound, whereby the energy transferred tosaid torsion spring from the cage is stored in said torsion spring aslong as said coupler connects said axle thereto, and means for actuatingsaid coupler to disconnect said axle from said torsion spring forrelease of the energy therein to temporarily augment the drive motor inaccelerating the gun to operating speed.

2. The brake-starter device as defined in claim 1 wherein said torsionspring includes a torsion rod having one end disposed within saidhousing and journaled thereto with the opposite end extending outsidesaid housing, a torsion tube encasing the portion of said torsion rodextending outwardly from said housing with the outer ends of said tubeand rod being securely joined, and a flange for anchoring the oppositeend of said torsion tube to said housing.

References Cited in the file of this patent UNITED STATES PATENTS2,390,401 Trotter Dec. 4; 1945 2,480,212 Baines Aug. 30, 1-949 2,849,921Otto Sept. 2, 1958

